Tool-holder



(No Model.) Y

N. H. SNIDER.

i TOOL HOLDER. No. 257,400. 'Patented May 2,1882.

wnesses. QYWEWEOL* 4,7 Mja UNITED STATES PATENT OFFICE.

NICHOLAS H. SNIDER, OF PITTSBURG, PENNSYLVANIA.'

TOOL-HOLDER.

SPECIFICATION forming part of Letters Patent No. 257,400, dated May 2,1882. Application filed January 9, 1882. (No model.)

To all whom it may concern.:

Be it known that I, NICHOLAS H. SNIDER,

of Pittsburg, in the county ot' Allegheny and State of Pennsylvania,have invented a new and useful Improvement in Tools for DressingGrindstones; and I do hereby declare the following to be a full, clear,and exact description thereof.

The grinding-faces of grindstones have heretofore been dressed orfinished in the following manner: The stone, having been previously cutto the general shape required, is mounted upon a revolving shaft in asuitable frame. The tool used to dress the face is a ilatrectan gularstrip of steel otsufticien t length to be held, and from iive-eighths ofan inch to two inches wide. This tool or bit has been secured in a boxor holder by means of a setscrew, with one end projecting from the box.about one-quarterot' Van inch, and the holder rested upon thecross-timber of the grindstone frame or housing, and presented to theswiftly-revolving face of the grindstone in the same manlief as the toolof the turner is presented tothe work on his lathe. The hard granularsurface of the stone wears the steel bit of the tool off very rapidly,and then it has to be advanced in its holder. This neccssitates thecessation of the work, the unscrewing of the set-screw, and theadvancing of the bit. 'As this operation is a frequent and comparativelya slow one, the loss ot" time and power is considerable.

My invention consistsin an improved holder which enables me to make theadjustment with ease and quickness and obviates the use of aclamping-screw.

To enable others skilled in the art to make and use my invention, I willnow describe it by reference to the accompanying drawings, in WhichFigure 1 is a side view, partly in section, of my improved holder, andillustrates the manner of inserting and adjusting the bit.. Fig. 2 isalike view, showing the holder closed on the bit; and Fig. 3 is a frontend view.

Like letters of reference indicate like parts in each.

The holder is composed of a lia-t bar or body, a, having two perforatedlugs, b, one on each side, a rest, c, on the under side, and a handle,d, at the back end. Pivoted to and between the lugs is an eccentric orjaw, e, havsay, one-quarter of an inch. To insert the bit f the handlee2 is thrown up, as in Fig. l, un til the eccentricity c of the part eis turned out of the path ofthe bit. Then the bit isinserted and thehandle c2 is brought down onto thehandle d. This causes the eccentric eto bite on and clamp the bitfrmly in the holder. Y

Then it is desired to adjust the bit the handle c2 is thrown up and thebit drawn 0ntward. In use the projection-c is placed on the cross-bar ofthe grindstone-frame in front ofthe stone, and the holder is grasped inthe hand and presented to the face of the stone which is to be dressedinthe usual way.

My improved holder is efcient, simple, and cheap, and its use effectsasaving of time and power.

I am aware that an eccentric has heretofore been employed to clamp atool to its holder, and do not herein claim the same;V but lVhat I claimas my invention, and desire to secure by Letters Patent, ist 1. A bithandle or holder for giindstonedressers, said handle consisting ot' abed or rest for the bit, in combination with an eccelltric pivoted onthe bed and adapted to clamp the bit to the saine, the bed or rest andthe eccentric being provided with handles adapted to be brought togetheror parallel when the bit is held by the eccentric, substantially asspecified.

2. In a bit-holder for grindstonedressers, the combination ot' the bedorrest a, having the handle d, and provided with lugs at its forward end,and the eccentric e, pivoted between the lugs on the forward end ot' thebedl and provided with handle e?, substantially as and tor the purposespecified.

In testimony whereof I have hereunto set my hand this 4th day ofJanuary, A. 13.1882.

NICHOLAS H. SNIDER.

Witnesses:

T. AB. KEER, J AMES H. PORTE.

IOO

